Filament Winding Research Articles

Analysis of radial compression failure in CNTs-reinforced filament wound riser with a metal liner considering process parameters

The quality and performance of filament-wound risers may exhibit various characteristics due to the influence of the fabrication process parameters and materials. Researching the fabrication mechanism and product performance is crucial to enhancing product features. This paper aims to investigate the radial compression failure of carbon nanotubes (CNTs)-reinforced filament wound risers considering process parameters. Three process parameters, namely winding tension, winding speed, and curing time, were selected for experimentation based on the Box-Behnken design. The study comprehensively analyzed the failure modes of composite risers to reveal the compressive failure process and load-bearing capacity. Additionally, the parametric effects on the indexes were discussed. The results show that the composite riser initially experiences a gradual sinking at the upper and lower parts, outward on the left and right sides, and flattened shape as displacement increases. Interlaminar delamination is more likely to occur between specific angles, including ±15° and 90°, ±15° and ±55°, ±55° and ±45°. Besides, fracture failure is more probable in orthotropic layers with ±15° and ±45°. Parametric analysis revealed that the curing time has a more significant impact on crashworthiness.

Experimental characterization and modeling of cylindrical CFRP structures under quasi-static multiaxial loading conditions

An experimental and numerical investigation of the cylindrical carbon fiber reinforced polymer (CFRP) structures under various loads including tension/torsion loading conditions has been conducted. Various boundary conditions and parameters were taken into account to check the impact of the shear component to obtain the result. The nonlinear shear model proposed by Chang has been implemented to take into account the softening effect of the stress-strain curve caused by damage accumulation. The computational model of the thin-walled tubes contains the geometrical architecture of the material, such as interweaving, which are characteristic of the parts made by filament winding technology. The studies were preceded by preliminary tests of the individual components to predict elastic properties based on the Abolin'sh micromechanical approach. The strength parameters were empirically delivered on the basis of the experimental results and used to determine the failure of the structure. The accuracy of the calibrated nonlinear shear model was validated using strain gauges and digital image correlation techniques. The strain distribution obtained from FEA was compared with that of the optical method. The damage distribution provided by FEA is exhibited in a similar manner to the real one captured by DIC. The proposed model provides a precise prediction of the CFRP tubes under quasi-static loading conditions proven by the experiments.

Quantitative Damage Monitoring of Filament Wound Composites by Using Machine Learning-Based Techniques

Quantitative Damage Monitoring of Filament Wound Composites by Using Machine Learning-Based Techniques

An innovative composite elbow manufacturing method with 6-axis robotic additive manufacturing for fabrication of complex composite structures

Filament winding method is the most commonly used method to produce profiles with different cross sections as composite product manufacturing. In this method, fiber material is wound with resin at different angles on a mold that has a suitable cross section shape. As a winding strategy, angled and helical winding can be done. Motion planning for this process is done with geodesic and nongeodesic theories. Requirement to use mold in the filament winding method increases the cost. Also, there is an obligation to helical windings. In winding of different layers, 90° angle cannot be given between the layers. To overcome all these constraints, UV curing can be achieved using photopolymer resin and continuous fiber glass fiber with the help of robotic additive manufacturing technology. Toolpath strategies for production has a key role in this work. As a tool path strategy, nonplanar slicing can be done and manufactured composite elbow in angular layers without mold. Then, under favour of 6-axis mobility of the industrial robot arm, layers can be obtained at exactly 90° angle. In addition, in this method, unlike other winding methods, internal voids, i.e. a filling rate, can be given within the cylindrical encircled layers. In order to verify whether the elbows produced with this method meet the requirements of the desired applications in the industry in terms of mechanical properties, at different filling rates (50%, 75%, 100%), winding turns (0 and 1/8), and different fiber densities (45%, 55% and 65%) 90° curved composite elbows were produced and their internal pressure strength tests were tested. Afterwards, an optimization study was carried out with the Taguchi method for the production parameters that will maximize the internal pressure strength. According to the results of the optimization study, it is seen that it is appropriate to choose the printing parameters that will obtain the highest internal pressure strength values for production with this method, 100% fill rate, 65% fiber density and 0° winding angle. The products made of this process have the advantage of easy-shaping, reasonable ratio of axial strength and encircled strength, specification easy-unifying, stable product quality.

Three-Dimensional Analysis of Porosity in As-Manufactured Glass Fiber/Vinyl Ester Filament Winded Composites Using X-Ray Micro-Computed Tomography

AbstractFilament winding is a technique to manufacture tubular composite structures and, therefore, is among the most appealing techniques for fabricating critical structures such as hollow tubes. Despite the recent advances, these structures are prone to a varying degree of porosity that may affect their mechanical performance. Therefore, the accurate detection and quantification of the manufacturing porosity is crucial. Micro-CT is most suitable for performing this activity at various scales. This work employs micro-CT for studying porosity inside an as-manufactured filament-winded composite structure. Void characteristics like volume, orientation, size, and relative volume fraction inside the hoop and helical layers are quantified inside a representative curved panel extracted from a glass fiber-vinyl ester tubular composite structure, which has not been studied in detail previously. It was observed that most voids are present in the matrix region. The voids are elliptical rod-like and spherical, with the latter present in the helical layers, which also host the majority of voids and the highest void volume fractions. The voids are highly aligned along the fiber orientation direction with higher misorientations for helical layers than the hoop layer. Large voids in base layers were created due to gaps formed during the winding process. Hence, the main goal of this study is to measure the voids' characteristics and the volumetric fraction during the stacking of filament wound hoop and helical layers during a generic filament winding pattern. The data can be further exploited as input for modeling filament winded composites in the presence of voids by researchers.

Hydrothermal aging effect on crushing characteristics of intraply hybrid composite pipes

In this study, the crushing properties of hybrid glass, basalt, and carbon fiber-reinforced composite pipes under a hydrothermal aging environment were investigated. Hybrid and non-hybrid composite pipes manufactured by filament winding technique were immersed in distilled water and seawater at 30 °C for four months. The water sorption parameters of the samples were calculated theoretically and weighed experimentally. Dry and aged pipes were subjected to quasi-static axial compression to examine aging effects on the crushing properties. The experimental weighing results showed that all composites exhibited a Fickian-like water absorption line. The non-hybrid basalt pipes were the most water-absorbing among all groups. In addition, the results proved that the hybridization effect in pipes is highly effective on water absorption parameters. In line with the results of non-hybrid pipes, hybrid pipes containing basalt fiber absorbed more water than other hybrid ones. Additionally, pipes aged in different environments showed that composite pipes absorbed more distilled water compared to seawater. Also, it was found that hydrothermal aging having adverse effects on the crushing characteristics of the pipes led to significant decreases. This can be explained by the degradation of the fiber–matrix interphase due to aging. However, maximum specific energy absorptions were achieved from non-hybrid carbon pipes regardless of environmental conditions. Also, the hybridization enhanced the crushing properties of the non-hybrid pipes that have lower characteristics. Additionally, it can be said that hybrid samples providing better stability in crushing showed better mean crushing load values since they mostly had a progressive crushing mode. The maximum mean crushing loads were obtained from the unconditioned hybrid GC samples as 36.2 kN which was 9.5 % and 34 % higher than unconditioned hybrid CB and BG samples. In conclusion, the study proved that the samples with low crushing properties can be improved by hybridization even if they are subjected to harsh environmental conditions.

Design and manufacture of a Type V composite pressure vessel using automated fibre placement

Automated fibre placement (AFP) can improve composite pressure vessel design by enabling selective reinforcement and allowing a wider range of fibre orientations than the traditional filament winding process. This paper presents the development of an AFP Type V composite pressure vessel with a design working pressure of 4.22 MPa made using a novel collapsible mandrel. The design process is presented along with a thickness control strategy for the AFP parts using ply drops. The tank was manufactured, and the thickness was validated using 3D scanning. The masses of the AFP parts were also measured to within 2.23% of the predicted values. The finished tank was hydrostatically pressure tested to understand the leakage behaviour. Defects and difficulties encountered in this prototype are discussed and opportunities for future work and improvements have been identified.

Analytical method for deformation and stress calculation of bell-and-spigot joints in PVC-U pipes

The stable operation of water supply pipelines relies significantly on the structural safety of pipe joints. A novel analytical pipe joint structural calculation method based on the Novozhilov thin shell theory was proposed to calculate the deformation and stress of bell-and-spigot joints in unplasticized polyvinyl chloride (PVC-U) pipes under internal pressure. An equivalent stress index was established to investigate and evaluate the safety performance of pipe joints. The effects of various factors, including spigot insertion depth, the clearance between the bell and spigot, internal pressure, and different pipe nominal outside diameter (DN) and nominal pressure (PN) series, on the maximum equivalent stress of pipe joints, were thoroughly analyzed. The results indicate that the maximum equivalent stress under nominal pressure is located on the inner surface of the bell and consistently exceeds the design stress. The influence of spigot insertion depth on the maximum equivalent stress is minimal. However, as the clearance value between the bell and spigot decreases and the internal pressure increases, the maximum equivalent stress increases significantly. Pipes with smaller DN and PN series result in a higher maximum equivalent stress at the joint. The analytical method indicates that increasing pipe thickness and reinforcing the bell with continuous carbon fiber filament winding are two potentially effective methods to enhance the mechanical performance of the joint and reduce the maximum equivalent stress. This study's findings offer valuable theoretical support for designing and selecting joints in PVC-U pipelines.

Hybrid Aluminized Fiberglass Reinforced Composite Pipes: A Framework for Safety Use in Industries

Introduction: Polymer matrix composites have been utilized in various industries due to their low cost and good strength-to-weight ratios. AIM: This study aims to investigate the effectiveness of filament-wound fiber-reinforced polymer composite pipes. The focus is on aluminized fabric tubes, which are flexible and heat-resistant tubes made from a glass fabric and laminated with a layer of aluminum. AIM: This study aims to investigate the effectiveness of filament-wound fiber-reinforced polymer composite pipes. The focus is on aluminized fabric tubes, which are flexible and heat-resistant tubes made from a glass fabric and laminated with a layer of aluminum. Method: These tubes offer unique properties that make them suitable for various applications, especially in environments with high temperatures or exposure to radiant heat. Fiber Reinforced Plastic (FRP) pipes are highlighted for their lightweight, easy transportation, low maintenance, corrosion resistance, design flexibility, and anti-freezing performance. The study delves into the use of aluminized glass fiber for high-temperature applications, with a specific focus on enhancing high-temperature withstanding properties. Result: In addition, the present research also conducts tests to study the structural strength of normal glass fabric tubes and aluminized glass fabric tubes. The fabrication of composite pipes is achieved through a filament winding process with a zero-degree winding angle using a manually operated filament winding machine. Mechanical testing and Finite Element Analysis (FEA) simulations using ANSYS® are also performed to compare glass fiber-reinforced plastic pipes with hybrid aluminized fiber-reinforced plastic pipes. Conclusion: The application of aluminized glass fiber in both the internal and external layers of the pipes improves the pipe’s strength and ability to endure high temperatures.

Quasi-classical coherent states of a charged particle in a magnetic field with accounting for viscous losses

A quasi-classical approach is proposed for describing the motion of a charged particle in a magnetic field, taking into account irreversible losses due to the macroscopic viscosity of the medium. The wave function of a charged particle corresponding to its quasi-classical coherent state is found. It is shown that viscosity leads to an irreversible collapse of the wave function in directions perpendicular to the magnetic field. At the same time along the magnetic field the wave function experiences irreversible spreading up to a certain static limit. Thus, in the transverse directions a viscous medium and a magnetic field behave like a classical measuring device. In the longitudinal directions the signs of the quantum Zeno effect are visible. As a result of such anisotropic quantum dynamics the wave packet of the probability density takes the form of a thin filament wound around a magnetic field. The length of the filament is determined by the limiting value of the uncertainty of the longitudinal coordinate of the particle. In turn, this asymptotic uncertainty contains the information about its initial value, about the mass of the particle, and about the properties of the viscous medium.

An integrated structure of air spring for ships and its strength characteristics

Abstract The increasing demand for the impact resistance of ships entails the excellent impact resistance and deformability of air spring (AS) for ships under high internal pressure. However, an AS of traditional structure is difficult to satisfy such new demand since it is designed with only 10 mm maximum deformation under high internal pressure and strong impact. For this reason, an integrated structure of filament winding reinforced bellows is proposed to ensure the structural strength at the connection of AS bellows and flanges under strong impact and high internal pressure. On this basis, a parameterized design of integrated bellows strength is explored, and we analyzed how the strength of the bellows was affected by the parameters of geometrical structure, material features, and filament winding. As proved in tests, the integrated structural design of the bellows could ensure the strength of AS under strong impact and high internal pressure, and the test result perfectly matches with the calculated strength of the integrated bellows as well as the optimized design.

3D winding path modeling of overwrapped pressure vessels with novel mesh-based directional projection and normal adaptive convex helix algorithms

Filament winding is a technique that precisely places continuous fibers along a preset path on a rotating mandrel. However, traditional 2D winding paths based on the original mandrel surface ignore the effect of thickness stacking on doffing points. To physically simulate the build-up of tows on the mandrel, a novel numerical method, including the mesh-based directional projection (MDP) and normal adaptive convex helix (NACH) algorithms, is proposed. The MDP algorithm is employed to sort out tow overlaps in the thickness direction, and is 200 times more efficient than the existing algorithms, such as the backward search algorithm. Subsequently, the “cliffs” generated in the overlap removal process are smoothed by the NACH algorithm. Furthermore, the advantages of these two algorithms in terms of efficiency, reliability, and universality are discussed in detail. In summary, a method for developing a physical-based 3D path and ever-updating workpiece contour of pressure vessels is proposed, which serves as an essential reference for high-precision winding and workpiece shape optimization.

Investigation of crack propagation in filament wound composite samples of Mode-I by using acoustic emission technique

A common industrial method of fabricating composite structural is filament winding, which is widely used to manufacture axisymmetric components. One of the most prevalent damage mechanisms in these composite structures is delamination, which occurs in various types of loading. In this research, the mechanical behavior and propagation of the initial crack of Mode-I in carbon/epoxy filament wound (FW) composite curve beams have been investigated via the acoustic emission (AE) method. For this purpose, at first, a composite tube was made with considering the artificial interlayer separation, and the beam specimens were cut from the longitudinal direction. At first, the initiation of the failures was determined using the AE method. Then, the growth and spread of interlayer delamination were investigated by the energy of AE signals and the sentry function. By determining the speed of the AE waves and providing a method to filter unwanted signals, the momentary position of the interlayer delamination tip during growth is predicted. The results showed that the fiber bridging phenomenon was due to the penetration of the two regions adjacent of the separation interface, and the fiber bridging length considerably affected the Mode-I delamination fracture toughness. In addition, the fracture toughness increased as the fiber bridging zone enlarged. Finally, good agreement was observed between the fracture toughness values obtained from the AE method and those found in the standard ASTM D5528.

FEA and experimental ultimate burst pressure analysis of type IV composite pressure vessels manufactured by robot-assisted radial braiding technique

Composite pressure vessels (CPVs) are lightweight and high-strength containers that can be used for the storage of compressed gases, including hydrogen. While hydrogen is a promising alternative energy source, storage of hydrogen comes with its significant challenges which requires a need for the efficient production of CPVs. Most commonly, CPVs are manufactured using filament winding technology. Due to the rise in the need for pressure vessels, there is a need for alternative high-throughput manufacturing techniques. Braided, in comparison to filament winding, has a high throughput and is less research manufacturing technology for CPVs. In this study, the applicability of braiding for the manufacturing of CPV is researched. Two types of 2D braids, namely the conventional and unidirectional, braiding were studied for their application in such structures, 24K and UD tanks, respectively. Dry carbon fiber (T700S – 24K) and HDPE liner were used to manufacture two different types of composite pressure vessels (CPVs), by robot-assisted radial braiding technique. After the preform of the braiding process was finished, CPVs were cured with a vacuum infusion process (VIP) by using a mold system. Produced braided CPVs were subjected to a hydrostatic burst test in order to determine their ultimate burst pressure point. Finite element analysis (FEA) was used to optimize and correlate experimental burst pressure test results. Ansys ACP was utilized to design composite structures by dividing both tanks’ domes into sub-sections. Results suggest that the experimental burst pressure test of 24K and UD tanks were identified as 200 bar and 150 bar, respectively. UD vessel ruptured close to the dome, whereas the 24K fracture point was located in the center of the dome. UD braided CPV was shown to have a smaller apparent burst deformation (rupture) scale than 24K CPV. In comparison to 24K, the UD braided CPV is 5.7% lighter and requires 20.9% less carbon fiber in production. FEA results were consistent with experimental results in terms of the burst pressure point. For both 24K and UD, the fiber failure starts at the point where the cylinder section and boss system are connected under pressure, and fiber failures continue to progress steadily as the pressure increases.

An Improved Finite Element Model to Study Stress Concentration Around an Elliptical Cutout in Pressure Vessel : Application- Part II

The application of finite element method (FEM) to the solution of cutout and inclusion problems in Filament Wound Fibre Reinforced Plastic (FWFRP) pressure vessel is considered. The analysis of pressurised laminated composite shell, which can be regarded as a heterogeneous body consisting of a finite number of orthotropic layers bonded together, with an elliptical hole is carried out. The influence of uniform shear force distribution along the hole boundary is studied. The numerical results of pressurised laminated composite shell with transverse elliptical hole filled by edge bonded elastic cover are also presented. Predicted stress distribution through the thickness of composite shell with cutout/inclusion at critical locations on the hole boundary is presented in graphical form and discussed.

Extension of Computational Co-Design Methods for Modular, Prefabricated Composite Building Components Using Bio-Based Material Systems

Robotic coreless filament winding using alternative material systems based on natural fibers and bio-based resin systems offers possible solutions to the productivity and sustainability challenges of the building and construction sector. Their application in modular, prefabricated structures allows for material-efficient and fast production under tightly controlled conditions leading to high-quality building parts with minimal production waste. Plant fibers made of flax or hemp have high stiffness and strength values and their production consumes less non-renewable energy than glass or carbon fibers. However, the introduction of natural material systems increases uncertainties in structural performance and fabrication parameters. The development process of coreless wound composite parts must thus be approached from the bottom up, treating the material system as an integral part of design and evaluation. Existing design and fabrication methods, as well as equipment, are adjusted to emphasize material aspects throughout the development, increasing the importance of material characterization and scalability evaluation. The reciprocity of material characterization and the fabrication process is highlighted and contributes to a non-linear, cyclical workflow. The implementation of extensions and adaptations are showcased in the development of the livMatS pavilion, a first attempt at coreless filament winding using natural material systems in architecture.

A novel model for buckling of composite shell: Ring stiffened shell and stiffened shell with cutout under hydrostatic pressure

Focusing on buckling problem under hydrostatic pressure of ring stiffened shells and shells with stiffened cutout fabricated by filament winding process, a new form of equilibrium equations is given in this paper based on high-order shear deformation theory (HSDT). A novel theoretical model is proposed based on Messager's model of geometrical imperfection. The model contains both ring stiffened shell model (RSSM) and stiffened shell with cutout model (SSCM). In this model, changes in the shells' thickness z˜k(x,y),k=1,2,…,n are described using a Fourier series representation, which is included in HSDT stiffness matrix A, B, D, E, F, H. To evaluate the critical buckling pressure pcr, the model is applied and compared with the conventional stiffened cylindrical shell (SCS) model. The results demonstrate a significant reduction in error, ranging from 71.08% to 81.22%, when using the proposed model for shells stiffened by a ring stiffener in the middle, as compared to the SCS model. This highlights the enhanced accuracy provided by the proposed model. The results indicate that small stiffened cutouts in thin shells and large stiffened cutouts in moderately thick shells have relatively small influence on the critical buckling pressure. Conversely, the presence of a ring stiffener in the middle has a more pronounced effect.

Acoustic Emission-Based Analysis of Damage Mechanisms in Filament Wound Fiber Reinforced Composite Tubes.

This study investigates the mechanical behavior and damage mechanisms of thin-walled glass/epoxy filament wound tubes under quasi-static lateral loads. The novelty is that the tubes are reinforced in critical areas using strip composite patches to provide a topology-optimized tube, and their damage mechanisms and mechanical performance are compared to that of un-reinforced (reference) tubes. To detect the types of damage mechanisms and their progression, the Acoustic Emission (AE) method is employed, accompanied by data clustering analysis. The loading conditions are simulated using the finite element method, and the results are validated through experimental testing. The findings confirm that the inclusion of reinforcing patches improves the stress distribution, leading to enhanced load carrying capacity, stiffness, and energy absorption. Compared to the reference tubes, the reinforced tubes exhibit a remarkable increase of 23.25% in the load carrying capacity, 33.46% in the tube's stiffness, and 23.67% in energy absorption. The analysis of the AE results reveals that both the reference and reinforced tubes experience damage mechanisms such as matrix cracking, fiber-matrix debonding, delamination, and fiber fracture. However, after matrix cracking, delamination becomes dominant in the reinforced tubes, while fiber failure prevails in the reference tubes. Moreover, by combining the AE energy and mechanical energy using the Sentry function, it is observed that the reinforced tubes exhibit a lower rate of damage propagation, indicating superior resistance to damage propagation compared to the reference tubes.

On the winding pattern influence for filament wound cylinders under axial compression, torsion, and internal pressure loads

An intrinsic characteristic of components manufactured by the filament winding process is a winding pattern formation during the processing. This paper aims at unlocking and understanding how the winding pattern influences the mechanical behaviour of filament wound cylinders under different boundary conditions. To realize this, a series of finite element models followed by an original geometric approach to generate the pattern are herein developed. Four different patterns and six different winding angles are modelled. These are also modelled by varying the number of layers towards understanding whether there is a correlation between the pattern and the number of layers or not. Three loading cases are considered: axial compression, pure torsion, and internal pressure. Key results reveal that the more layers are stacked to the cylinder, the less impactful is the winding pattern to all loading cases herein investigated.

Analysis and optimization of junction between cylindrical part and end dome of filament wound pressure vessels using data driven evolutionary algorithms

The junction between cylindrical part and end dome is the most critical place of the filament wound composite pressure vessels because the shear forces and bending moments occur in this area. The strength analyses of junction between cylindrical part and different types of known end domes based on influence coefficients method were performed for filament wound composite pressure vessels manufactured using glass-epoxy and carbon-epoxy composites. Four known end domes were considered that is, a spherical shell, a geodesic-isotensoid shell, a shell based on minimizing of the Tsai-Hill’s strength criterion and shell designed in authors’ previous work (Hoffman 1 shell). Moreover, the study is also dealing with design of optimal end dome shape which takes account to the junction area. Finding of optimal end dome shape was based on data-driven evolutionary algorithms. Using input dataset from the analytical simulation surrogate models were created using Evolutionary Deep Neural Nets (EvoDN2) algorithm. The multicriterial optimization procedure was performed using Constrained Reference Vector Algorithm (cRVEA) optimization algorithm. Results indicates that the optimal end dome shape highly depend on material properties.